Ladder



.. Patented Nov. I8, 1952 LADDER Hudmon ,S. Langley and Pasco R. Langley, Birmingham, Ala.

Application March 27, 1947, Serial No. 737,454

Our invention relates to an improvement in connecting means for securing cross members to spaced longitudinally disposed members and, while not limited thereto, is especially adapted for securing the rungs of ladders to the side members thereof.

One object of our invention is to provide an extremely strong joint for securing the rungs of ladders to the longitudinally extending side members which shall be economical of manufacture, highly eflicient as a securing means for the ends of the rungs, and effective to prevent relative movement between the side members when the ladder is assembled.

Another object is to provide a joint for ladder rungs in which the rungs are rigidly secured to the runners or side members by a single fastening means such as a rivet or bolt.

A further object is to provide a ladder in which the rungs thereof are reinforced at their ends against shear stresses imposed on the same by the connecting means securing them to the side members.

A ladder embodying features of our invention is illustrated in the accompanying drawing forming a part of this application in which- Fig. 1 is a plan view of a ladder embodying our improved joint;

Fig. 2 is a detail sectional viewy taken generally along line II--II of Fig. 1;

Fig. 3 is a perspective view of our improved joint as viewed from the inside of one of the runners or side members;

Fig. 4 is a fragmentary plan view of a modified form of our invention; and,

Fig. 5 is a detail view taken along line V-V of Fig. 4.

Referring now more particularly to Figs. 1, 2, and 3, we show a ladder I Il having side members which preferably are formed of channels I I and I2 with the flanges thereof inturned. For the sake of lightness, the channels I I and I2 may be made of aluminum or other light weight material, and may be rolled or extruded shapes of standard commercial dimensions. The rungs I3 preferably are formed of sections of tubing and are secured at each end to the side members I I and I2 by our improved connecting means which now will be described.

As best seen in Figs. 2 and 3, we provide at the end of each rung I3 a short length of channel I4, of such Size as to fit snugly between the flanges I 6 and Il of the side channels II and I2, and having its own flanges abutting the inside of the base I of the side channel. The

base I9 of the channel I4 is provided with a hole 20 through which passes the end of the rung I3.

In order to utilize light weight tubing for the' rungs I3, we provide at each end of the rung a reinforcing member comprising a short section of tubing 2I, telescoped within the ends of the rung. A rivet 22 passes through the flanges of the side channel and the channel I4, and through the rungs I3 and the telescoped insert 2I, thus to secure the parts together.

It Will be noted that the base I9 of the channel i4 forming one of the supports for the end of each rung, is spaced from the base I8 of the side member I I. The rivet 22 acts as both a second supporting means for the end of the rung as well as a securing means therefor. The rungs therefore are supported adjacent their ends at two points spaced along the longitudinal axis of the rung, and we have found that this construction adds considerable rigidity to the ladder as a whole. Further, it will be apparent that the short section of tubing 2I, which preferably is forced into the end of the rungs with a tight fit, takes a considerable portion of the shear load imposed on the rungs by the rivet.

Referring now more particularly to Figs. 4 and 5, we show a slightly modified form of our invention in which the rungs I3 pass through an opening 24 formed in the base 25 of a section of channel 26. The channel 26 is slightly longer than the channel I4, shown in Figs. l, 2, and 3, and in addition to the rivet 22 directly connecting the end of the rung, we provide a second 4 rivet 2T which passes only through the flanges of the side and support channels II and 26. This arrangement adds further strength to the joint and the elongated channels 26 further strengthen the side members against bending at the point of stress. With the exception that the channel 25 is slighly longer than the channel I4, it is identical with the latter. The rung I 3, insert 2 I, and the rivet 22 holding the parts assembled are the same as shown in Figs. 1, 2, and 3.

From the foregoing it will be apparent that we have devised an improved joint for ladders and the like which is extremely simple of manufacture, and which nevertheless serves to secure the cross members rigidly to the longitudinally extending side members. In actual practice we have found that a ladder constructed according to our invention is highly satisfactory in every way and that our joint eliminates relative shifting movement between the side members, thereby resulting in a very rigid unit. Further it will be noted that the channels I4 and 26 lie Wholly within the confines of the projecting inwardly disposed flanges of the side channels, thus aording a smooth construction free of projecting corners. Also, While We have described and illus- 'trated our invention in connection with ladder constructions it will be obvious that the same is equally applicable to other constructions in which it is desired to secure the ends of members to other members, and the term ladder as used in the claims is to be understood as including such other constructions.

While We have shown our invention in but two forms, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various other changes and modifications, without departing from the spirit thereof, and We de-h sire, therefore, that only such limitations shallk be placed thereupon as are specifically set forth in the appended claim.

- What We claim is:

In a ladder, side members extending the length of the ladder and comprising channels with the anges thereof inturned, cross members forming rungs and Vhaving their ends abutting the inner sides of the bases of the side channels, a support for each of the ends of the rungs comprising a short length of channel tting snugly between the flanges of the side members and with the ends of its own flanges abutting the base of the side channels, there being an opening in the base of the support channel for passing the end of the rung, and securing means passing through the anges of both channels and the end of the rung rigidly securing the same together and holding each end of the rung against the inner side of the base of its associated side channel.

HUDMON S. LANGLEY.

PASCO R.

REFERENCES CITED The following references are of record in the rrile of this patent:

UNITED STATES PATENTS Number Name Date Y 585,129 Steck June 2-2, 1897 870,334 Adler Nov. 5, 1907 1,232,221 lChesebro July 3, 1917 1,592,109 Jacobs July 13,1926 1,724,836 Heinrich Aug, 13, 1929 2,040,977 YCarbis May 19,1936 2,153,127 Arps Apr. 4, 1939 2,173,525 Wallace Sept. 19, 1939 2,416,950 Pohrman Mar. 4, 1947 FOREIGN PATENTS Number Country Date ,175,157 Great Britain Feb. 16, 1922 497,082 Great Britain Mar,8, 19.37 

